【摘要】 目的　探讨辣椒素(capsaicin)对大鼠三叉神经节神经元瞬时外向钾电流(IA)和延迟整流钾电流(IK)的 不同影响。方法　采用全细胞膜片钳方法。结果　对于辣椒素敏感神经元,辣椒素可选择性、剂量依赖性地抑制其 IA电流,但辣椒素对IK无明显选择性作用;对于辣椒素不敏感神经元,辣椒素对IA和IK均无作用,且对IA和IK激活动 力学亦无影响。结论　辣椒素可选择性抑制对其敏感的三叉神经节神经元IA,这可能是初次应用辣椒素时其致痛 作用的原因之一。更多还原

【Abstract】 Aim To investigate the effect of capsaicin on I A and I K in cultured rat trigeminal ganglion (TG) neurons. Methods Whole-cell patch clamp technique was used to record the I A and I K before and after capsaicin perfusion at different concentrations. Results In capsaicin-sensitive (CS) neurons,capsaicin was shown to selectively inhibit I A in dose-dependent manner,the IC 50 was 0.99 μmol·L -1. Yet capsaicin showed no inhibitory effect on I K,capsaicin (10 μmol·L -1) only slightly inhibited I K by 13.2%. In capsaicin-insensitive (CIS) neurons,capsaicin (1 μmol·L -1) showed no significant inhibitory effect on I A and I K,capsaicin (10 μmol·L -1) only slightly inhibited I A and I K by 16.8% and 15.3%,respectively. Neither 1 μmol·L -1 nor 10 μmol·L -1 capsaicin showed effect on the G-V curve of I A and I K. Conclusion Capsaicin was found to selectively inhibit the I A current in CS neurons,and this effect may contribute to hyperalgesia when capsaicin was first used.更多还原